Jaw crushers are machines that typically are stationed at construction sites such as where buildings are being demolished or roads are being built or repaired. The jaw crushers are used to reduce rubble or other materials from a larger to a smaller size. Material from these constructions sites may be placed into the jaw crusher, crushed into a suitable size by the jaw crusher and a further processing machine, and then reused at this particular construction site. This allows for a quick, inexpensive supply of needed materials along with the reduction of waste to the environment.
Another important use of jaw crushers is in assisting in the cleaning up and the reduction of waste in our society. Jaw crushers may reduce objects from a larger to a smaller size in order to recycle and/or store waste material. Jaw crushers assist in recycling used concrete, asphalt, brick, cinder block, demolition debris, glass, and any other substances that are hard and brittle. Jaw crushers are also used for crushing rock and other natural substances. The recycling of these materials is an increasingly important aspect in the cleaning and preservation of our environment.
A typical jaw crusher uses a diesel/hydraulic system in order to operate. It is often the case that other pieces of machinery that work in conjunction with the jaw crusher to reduce material from a base size to the desired size also have their own diesel/hydraulic systems. For instance, a front end loader may load material into the jaw crusher, and a screening device may be present to reduce the size of the material that is ejected from the jaw crusher. Further, a conveyor system is commonly employed to transport material to and from the jaw crusher. In addition to the increased cost of running these separate systems, operation of such numerous diesel/hydraulic systems also negatively impacts the environment.
A jaw crusher includes a generally V-shaped crushing space that is formed between two crushing plates. Typically one of these plates is a fixed plate while the other plate is movable. It is common for an eccentric shaft to be provided on the jaw crusher. The movable plate is in communication with this eccentric shaft, and rotation of the eccentric shaft causes a corresponding movement of the movable plate. Material is placed into the upper portion of the crushing space. This material, for instance a stone, is then crushed between the two crushing plates by relative movement of the crushing plates. The broken material then falls due to gravity into a subsequently narrower portion of the crushing space and is likewise reduced in size. Upon exiting the crushing space from the jaw crusher, the material is reduced to a size smaller than that when previously inserted.
In a typical jaw crusher, the movable plate transfers a great quantity of energy in a short amount of time into the material that is crushed between the two crushing plates. This energy is transmitted into the stone or other material and concentrates locally in a weak portion or interior area of the stone. This local concentration of energy allows for the stone to be crushed between the two crushing plates.
Some jaw crushers are provided with a wedge adjusting mechanism that may be used to toggle the distance between the two crushing plates. Such an adjustment of the distance between the crushing plates is effected when the jaw crusher is turned off. Such an adjustment of the distance between the two crushing plates will allow for varying output sizes of material to be realized.
Problems have occurred in jaw crushers when they are utilized in crushing softer materials, for example asphalt. It is sometimes the case that these softer materials are not pulverized into smaller pieces, but are instead pressed into a smaller, harder piece. Such pressing of soft materials presents a problem because they may become adhesively connected to one of the crushing plates. In such a situation, the sticking of material onto one of the crushing plates may prevent operation of the jaw crusher. This situation requires stopping the jaw crusher and removal of the jammed object. Crushing material that contains clay or other softer materials may necessitate the stopping of the jaw crusher at occasional intervals in order to scrape out the compacted clay from corrugations that may be present on the crushing plate. The pivotal crushing plate of some jaw crushers may be rotated in an opposite direction in order to remove this adhesively connected material from the crushing plate. Upon removal of this material, the crushing plate may be again rotated in the forward direction to once again pulverize material.
A jaw crusher is also designed in order to crush harder materials. In fact, jaw crushers may crush materials that contain steel. It is sometimes the case that material that contains steel when crushed by a jaw crusher separates from the steel upon being crushed. An example of some material that may be crushed by a jaw crusher include: rock, rubble, stone, boulders, concrete, asphalt, brick, block, glass, demolition debris, and the like.
In some jaw crushers, the most efficient mode of operation of the jaw crusher is to keep the crushing chamber full of material. Material may be fed into the crushing chamber of the jaw crusher by, for instance, a front end loader.
Jaw crushers are typically positioned at single locations in a construction site. Other pieces of machinery must be used in order to provide material to the jaw crusher to be crushed. Additional equipment must be employed in order to remove the material that is ejected from the jaw crusher, and must be used to further process the material into a desired size. Additionally, further equipment may be required in order to transport the ejected material from the jaw crusher into a desired location. All of the equipment and/or systems used to transport material to and from the jaw crusher, in addition to further process the material, require a source of power. Also, these systems must be maintained and often operated by a user. Elimination of these systems would prove beneficial in that less energy, man power, and/or power sources would be needed to complete the process.